Vanes for rotary pumps and motors

ABSTRACT

A fluid pumping vane including a body member having arcuate end surfaces in close proximity to surfaces of a pump housing defining a fluid chamber. The vane body member, having front and rear surfaces, also includes resilient lips terminating in free ends, the lips overlying the arcuate surfaces of the body member and being inherently biased into engagement with the housing surfaces to provide a tight seal. In preferred form, the body member can be composed of aluminum, graphite, bakelite, or similar material, while the sealing lips are composed of a low friction resilient plastic material such as polytetrafluoroethylene or any other low friction fluoropolymer. The sealing lips extend toward the front surface of the vane body so that high pressure gases enter the area between the arcuate end surfaces of the body and the lips and further urge the lips into engagement with the housing surfaces. The plastic material sealing lips can be integral with the vane body member, they can be attached to a surface of the vane body member by a polyimide type adhesive or they can be formed to include a tongue portion received in a mating retaining groove in the body member.

United States Patent 1191 Jacobs [45] Mar. 26, 1974 VANES FOR ROTARY PUMPS AND MOTORS [75] Inventor: James W. Jacobs, Dayton, Ohio [73] Assignee: General Motors Corporation,

Detroit, Mich.

[22] Filed: Oct. 13, 1972 [21] Appl. No.: 297,400

[ 7] ABSTRACT A fluid pumping vane including a body member having arcuate end surfaces in close proximity to surfaces of a pump housing defining a fluid chamber. The vane body member, having front and rear surfaces, also includes resilient lips terminating in free ends, the lips overlying the arcuate surfaces of the body member and being inherently biased into engagement with the housing surfaces to provide a tight seal. In preferred form, the body member can be composed of aluminum, graphite, bakelite, or similar material, while the sealing lips are composed of a low friction resilient plastic material such as polytetrafluoroethylene or any other low friction fluoropolymer, The sealing lips extend toward the front surface of the vane body so that I 56] References Cited high pressure gases enter the area between the arcuate UNITED STATES PATENTS end surfaces of the body and the lips and further urge I the lips into engagement with the housing surfaces. 2 i The plastic material sealing lips can be integral with 625960 7/1899 P212? 8 d 418/148 the vane body member, they can be attached to a sur- 2 853 978 9/1958 Smyseriiiii 1:: 418/153 face Vane body member y a polyimide ty e ad- 636,478 4/1953 Smyser 418/153 hesive Or they can be formed to include a tongue tion received in a mating retaining groove in the body FOREION PATENTS OR APPLICATIONS member 107,811 1/1900 Germany 418/146 729,402 3/1966 Canada 418/153 695,746 8/1953 Great Britain 418/147 4 Claims, 7 Drawing Figures Primary Examiner-Carlton R. Croyle Assistant Examiner-John J. Vrablik Attorney, Agent, or Firm-Charles R. Engel 52' 4'6 /fl 77 f [0 7 g V T K Mg) o" 4 18C" k/y 225 {10 27c z I 360 :7 in a 1 VANES FOR ROTARY PUMPS AND MOTORS My invention relates to an improved vane structure particularly useful in a rotary fluid pump or motor. More specifically, the improved vane of this invention is useful in a rotary compressor of the axial vane type.

Rotary fluid machines, for efflcient operation, re quire a positive seal between relatively rotating members regardless of whether the machine is being utilized as a pump or as a motor. In one general form of rotary fluid machines, one or more vanes are used to provide a sliding sealed engagement between rotor and stator assemblies separating a fluid chamber within the motor housing into high pressure fluid areas and low pressure fluid areas. In a more specific form, namely, a rotary axial vane compressonat least one axially slidable vane is supported in a rotor so that both sides of the vane slidably engage housing cam faces and compress fluid in separate chambers formed on opposite sides of the rotor. The improved vane assembly of this invention has particular application in any type of rotary axial vane compressor and will be described in association with a machine of the aforementioned type compressing fluid in separatechambers on each side of the rotor.

The vane assembly according to this invention includes a body member having arcuate ends extending toward the housing cam faces so that the cam faces, the housing periphery and the rotor define fluid chambers on either side of the rotor. The vane is slidably sup ported in a rotor slot for axial movement relative to the rotor as regulated by the contour of the cam faces. Resilient sealing lips are attached to, or are integral with, the vane body member and each terminate in a free end and overlyingrespectively the arcuate end surfaces of the vane body member. The vane body presents a front surface and a rear surface during rotation of the rotor while compressing fluid and the sealing lips are. configured to extend toward the front surface of the body so that fluid pressurized by the vane enters a space between the vane arcuate ends and the sealing lip. The fluid in this space is effective to further urge the lip into engagement with the housing cam faces insuring a tight seal. The sealing lips also are formed of a suitable material such as a low friction fluoropolymer or like material so that they are inherently biased into engagement with the cam faces. The inherent characteristics of the material used to form the sealing lips and their being positioned to receive high pressure fluid both add to the urging of the lip into sealing engagement with the housing cam faces.

Accordingly a primary object of this invention is to provide a simply constructed vane member including sealing lips inherently biased into, engagement with compressor housing surfaces during operation of the compressor.

It is another object of this invention to provide a compressor vane assembly including sealing lips being inherently biased into sealing engagement with compressor housing surfaces and the lips being positioned to receive high pressure fluid aiding in the sealing engagement.

A further object of this invention is the provision of a fluid pumping vane including a body member capable of being formed of aluminum, graphite, bakelite, or other similar material, and including a mounting groove receiving a tongue on'a sealing lip member formed of a flexible plastic having resilient characteristics such as a low friction fluoropolymer.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, both as to its organization and method of operation, may be best understood by reference to the following description taken in connection with the accompanying drawings in which:

FIG. 1 is an elevational view partly in section illustrating a rotary axial vane type compressor incorporating the subject vane assembly.

FIG. 2 is a geometrically developed view of movement of the inventive vane assembly as it traverses one complete revolution through thefluid chamber within the compressor housing.

FIG. 3 is a fragmentary sectional view illustrating one embodiment of the subject vane assembly.

FIG. 4 is a fragmentary sectional view of an integral vane body and sealing lip. FIG. 5 is a sectional view of a modification of the vane assembly.

FIG. 6 is a fragmentary sectional view of a further modification of the vane assembly.

FIG. 7 is a sectional view of a modified form of securing the sealing lips to the vane body member in accordance with my invention.

Referring now to FIG. 1 of the drawings, a vane 10 constructed in accordance with this invention is shown positioned in a slot 12 formed in rotor 14 of an axial vane compressor 16. The compressor assembly 16 includes end plates 18 and 20, respectively, providing bearing surfaces 22 and 24 rotatably supporting portions 26 and 28 of shaft 30. The end plates 18 and 20 are received within a cylindrical body 32. Grooves 34 in the end plates receive O-ring seals 36 completing a fluid tight seal between the end plates and the cylindrical body 32. The end plates 18 and 20 include cam faces 38 and 40 which cooperate with the inner periphery 42 of the cylindrical body 32 to define a fluid chamber 44 within the compressor assembly 16. The rotor 14 divides fluid chamber 44 into fluid working chambers 46 and 48 as best illustrated in FIG. 2. The working chambers 46 and 48 connect with inlet passages 50 and discharge passages 52 containing ball check valves 54 regulating flow through exhaust passage 56. An inlet passage, not shown, is also provided in the compressor assembly 16. Rotation of shaft 30 rotates rotor 14 within the fluid chamber 44 and due to sliding engagement of vane end surfaces 58 with the cam surfaces 38 and 40, the vane 10 moves axially in the rotor slot 12 and compresses fluid in the working chambers 46 and 48 as illustrated in the developed view of FIG. 2.

The improved vane 10, which is the subject of my invention, is shown in FIG. 1 in association with the re tary axial vane type compressor 16 for purpbses of illustration only. The vane 10 can be used with various types of rotary machines. Also the illustrated axial vane compressor 16 is shown to include working chambers 46 and 48 on either side of the rotor 44. The vane 10 is equally applicable to a machine having a working chamber only on one side of the rotor, the only necessary requirement being that the machine be of a type utilizing a vane having an edge 58 in sliding engagement with a relatively movable cam surface thereby pressurizing fluid in a working chamber as volume of the chamber changes with relative movement of the vane.

One form of my improved vane assembly is shown in FIG. 3. In this form a body member 60 can be composed of plastic, aluminum, graphite, bakelite, or similar material, and includes edges 58 arcuate in form. A sheet of sealing material 62 is adhered to a back low pressure face 64 of the body member 60 by a layer 66 of adhesive material, such as a polyimide type adhesive. The sheet of sealing material 62 can be of polytetrafluoroethelyne or any other low friction fluoropolymer and terminates in sealing lips 68 having free ends 70. The low friction fluoropolymer, used to form the sheet of sealing material 62 in preferred form, has inherent characteristics such that the sealing lips 68 are continuously urged into engagement with cam faces 38 and 40 of compressor assembly 16. As previously mentioned, the body member edges 58 are arcuate in form and further they cooperate with the free ends 70 of the sealing lip 68 to form a space 72 therebetween. The space 72 opens toward a front side 74 of the body member 60 so as to receive fluid pressurized by the vane as it moves through the working chambers 46 and 48, the pressurized fluid also aiding in the engagement of the sealing lips 68 with the cam faces 38 and 40.

Another form of my improved vane assembly 10 is illustrated in FIG. 4. In this form the body member 60 and the sealing lip 68 are molded integral so as to define the space 72 facing toward the front high pressure face 74 of the body member 60. Of course, it is necessary in this configuration, that a low friction fluoropolymer be used to form both the body member 60 and the sealing lip 68 so that the lip 68 includes the desirable inherent characteristics biasing it into engagement with cam faces 38 and 40.

Another form of the invention is shown in FIG. 5, wherein body member 10 is formed containing a groove 76 receiving a mating tongue portion 78 on a sealing member 80 including sealing lips 68 for the purposes previously described. A somewhat similar form of my improved vane assembly 10 is illustrated in FIG. 6, wherein the body member 60 contains arcuate grooves 80 adjacent edges 58. The sealing lip 68 is integral with a bulbous tongue member 82 which mates with and is received in the arcuate groove 80 thereby securing the lip 68 to the body member 60.

FIG. 7 illustrates a further form of my improved vane assembly 10 wherein the body member 60 contains a recessed area 84 on the back face 64 and contains apertures 86. A sheet of sealing material 62 is placed over the recessed area 84 so that apertures 88 in the sheet align with apertures 86 in body member 60 as well as with apertures 90 in a retaining plate 92. Rivets 94 are inserted in the aligned apertures and are forged to secure the assembly together.

While I have shown and described particular embodiments of my invention it will, of course, be understood cations and alternative constructions as fall within the,

true spirit and scope of my invention.

I claim:

1. A vane assembly having application in a rotary fluid machine of the type including a housing having surfaces defining a fluid chamber, a rotor rotating in said chamber dividing it into separate fluid work chambers on each side of said rotor, said rotor having at least one vane assembly movably supported therein in sliding engagement with the housing fluid chamber surfaces when the rotor rotates relative to saId housing, the vane assembly comprising: a vane body having a front high pressure face and a rear low pressure face in relation to rotation of said rotor and having an arcuate surface at each end thereof adjacent said housing fluid chamber surfaces; a seal member secured to said rear low pressure face of said vane body and including sealing lips terminating in free ends extending over said vane body end arcuate surfaces; said sealing lips being inherently biased into engagement with said housing fluid chamber surfaces so as to define a space between said vane end arcuate surfaces and the free ends of said lips whereby fluid pressurized by said vane rotating in said work chambersenters into the space between the lips and the vane arcuate surfaces so that the lips are further biased into engagement with said housing fluid chamber surfaces providing a tight seal therebetween.

2. A vane assembly as described in claim 1 wherein said seal member is of a low friction fluoropolymer and is bonded to the back face of said vane body by a polyimide type adhesive.

3. A vane assembly as described in claim 1 wherein said vane body contains a depression in said rear low pressure face; a portion of said seal member being received in said depression; a retaining plate overlying the portion of said seal member in the depression; said body, said seal member and said plate having aligned apertures therethrough; and a plurality of rivets in said apertures fastening said seal member and said plate to said vane body.

4. A vane assembly as described in claim 1 wherein said vane body contains a flanged slot and said seal member is formed with a mating tongue received in the slot attaching said seal member to said vane body. 

1. A vane assembly having application in a rotary fluid machine of the type including a housing having surfaces defining a fluid chamber, a rotor rotating in said chamber dividing it into separate fluid work chambers on each side of said rotor, said rotor having at least one vane assembly movably supported therein in sliding engagement with the housing fluid chamber surfaces when the rotor rotates relative to saId housing, the vane assembly comprising: a vane body having a front high pressure face and a rear low pressure face in relation to rotation of said rotor and having an arcuate surface at each end thereof adjacent said housing fluid chamber surfaces; a seal member secured to said rear low pressure face of said vane body and including sealing lips terminating in free ends extending over said vane body end arcuate surfaces; said sealing lips being inherently biased into engagement with said housing fluid chamber surfaces so as to define a space between said vane end arcuate surfaces and the free ends of said lips whereby fluid pressurized by said vane rotating in said work chambers enters into the space between the lips and the vane arcuate surfaces so that the lips are further biased into engagement with said housing fluid chamber surfaces providing a tight seal therebetween.
 2. A vane assembly as described in claim 1 wherein said seal member is of a low friction fluoropolymer and is bonded to the back face of said vane body by a polyimide type adhesive.
 3. A vane assembly as described in claim 1 wherein said vane body contains a depression in said rear low pressure face; a portion of said seal member being received in said depression; a retaining plate overlying the portion of said seal member in the depression; said body, said seal member and said plate having aligned apertures therethrough; and a plurality of rivets in said apertures fastening said seal member and said plate to said vane body.
 4. A vane assembly as described in claim 1 wherein said vane body contains a flanged slot and said seal member is formed with a mating tongue received in the slot attaching said seal member to said vane body. 